01/29/2021

Amateur radio on the International Space Station (ARISS) and his partners fix a bug in the integrated NA1SS amateur station in the ISS Columbus module. However, the problem doesn’t seem to be with the radio equipment in Columbus. ARISS recognized the problem when contact with a school in Wyoming between ON4ISS on Earth and the astronaut Mike Hopkins, KF5LJG, at NA1SS had to be broken off if no downlink signal could be heard.

“Today was a difficult time for ARISS,” began ARISS International Chairman Frank Bauer, KA3HDO, in a message to the ARISS team on January 28th. Bauer explained that during a spacewalk on January 27 to install external cabling on the ISS Columbus module, the current coax cable installed 11 years ago was replaced with another one built by the European Space Agency (ESA) and Airbus. It contained two additional RF connectors to aid in commissioning the Bartolomeo Payload hosting platform installed on Columbus last spring.

“On January 26th before the EVA [extravehicular activity]Our next-generation Columbus radio system was switched off and the ISS-internal coaxial cable to the antenna was disconnected from the ARISS radio as a safety measure for the EVA, ”said Bauer. During the spacewalk, an external four-port coax lead replaced one with two RF connections.

“This change was made to enable ESA to connect ARISS and three other customers to Bartolomeo, compared to ARISS and one other RF customer,” said Bauer.

After the spacewalk was completed, the ISS crew restarted ISS amateur radio on Jan. 28, but no downlink reports for voice repeaters or APRS (Automatic Packet Repeater System) were heard. During a planned school contact at 1746 UTC, no downlink signal was heard either and the attempted contact had to be terminated.

“There is clearly a problem,” continued Bauer. “Further troubleshooting is required. It may be the new external RF cable that was installed during yesterday’s EVA. It could too [have been caused by] connecting and disconnecting the inner coaxial cable (RF). So the inner cable cannot yet be completely reduced. “

According to Bauer, the crew took photos of the coaxial cable and connector that are attached to the ARISS radio in the ISS. “Since the outside cable is a Bartolomeo cable and not an ARISS cable, we are working with ESA and NASA on another way,” he said. “NASA has published a Payload Anomaly Report on the subject. We spoke to representatives from both NASA and ESA. “

According to Bauer, ARISS asked its Russian team leader Sergey Samburov, RV3DR, whether ARISS could temporarily use the RS0ISS radio in the ISS service module for school contacts that are already planned until ARISS can solve the problem.

“On behalf of the ARISS International Board, the ARISS delegates and the entire team, I would like to thank you all for your enormous voluntary support from ARISS,” said Bauer. We will get through this and be more resilient as a result. ”